Head support device with bearing and elastic member

ABSTRACT

The disclosed suspension assembly (S) for carrying a magnetic recording head in close following relation to a recording disc includes an improved arrangement for supplying a load to the recording head. The suspension assembly (S) includes a flexible gimbal section ( 10   a ) for mounting the recording head and accommodating dampened pitch, roll and transverse movements. The head load arrangement comprises a flexible cantilevered spring tongue ( 10   b ) and an elongate rigid load member ( 20 ) that extends from the free end of the spring tongue to contact the suspension assembly (S) adjacent the recording head. The load member ( 20 ) is configured to cause the spring tongue ( 10   b ) to resiliently deflect by a predetermined amount, resulting in a predetermined head load being supplied through the load member to the recording head.

TECHNICAL FIELD

The present invention relates to a head support device used in a diskapparatus having a floating type head, for example, magnetic diskapparatus, optical disk apparatus, and magneto-optical disk apparatus,and a disk apparatus using the same.

BACKGROUND ART

A disk recording and reproducing apparatus (disk apparatus) such as harddisk drive (HDD) is designed to record and reproduce data on a recordingsurface of a disk as recording medium by means of a head. The HDD has ahead support device (also known as head actuator device or carriagedevice), and the head is supported by it in a floating state with aspecified interval above the disk recording surface, and is designed tomove in the radial direction above the disk, and such configuration andconstruction are proposed in various publications (for example, see page4 of Japanese Patent Laid-open Application No. H9-82052).

As an example of head support device of a conventional disk apparatushaving a floating type head, a head support device in a magneticrecording and reproducing apparatus such as HDD is explained byreferring to FIG. 19 which is a plan view of structure of essentialparts of magnetic recording and reproducing apparatus, and FIG. 20 whichis an essential perspective view explaining the structure and action ofhead support device.

In FIG. 19, a head support device 101 comprises a load beam 102 ofrelatively low rigidity, an elastic member 103, and a carriage 104 ofrelatively high rigidity, and a slider 105 mounting a magnetic head (notshown) is provided beneath an end of the load beam 102.

A magnetic recording medium 106 is designed too be rotated by a spindlemotor 107, and at the time of recording or reproduction of the magneticrecording and reproducing apparatus, the slider 105 is lifted from themagnetic recording medium 106 by a specified amount, owing to thebalancing relation between the buoyancy the slider 105 receives by theair stream generated by rotation of the magnetic recording medium 106and the thrusting force of the elastic member 103 of the head supportdevice 101 for forcing the slider 105 toward the side of the magneticrecording medium 106, that is, the magnetic head mounted on the slider105 is lifted from the magnetic recording medium 106 by a specifiedamount.

At the time of recording or reproduction of the magnetic recording andreproducing apparatus, the head support device 101 is rotated about asecond bearing 109 by the action of a voice coil 108 provided at theopposite side of the load beam 102 of the carriage 104, and the magnetichead mounted on the slider 105 is positioned against a desired track ofthe magnetic recording medium 106, thereby performing recording orreproduction.

Referring further to FIG. 20, the structure and action of the headsupport device 101 are explained. FIG. 20 is an essential perspectiveview of the section of the magnetic head in the head support device 101in FIG. 19.

In FIG. 20, the magnetic head (not shown) is provided at the oppositeside of the magnetic recording medium (not shown) of the slider 105provided at the lower side of one end of the load beam 102. Other end ofthe load beam 102 is folded, and an elastic member 103 is formed, andthe elastic member 103 is stopped at the carriage 104. To suppresschanges of load of the slider 105 on the magnetic recording medium dueto surface deflection or perpendicular motion of the magnetic recordingmedium, or manufacturing fluctuations in the distance between the slider105 and magnetic recording medium at the time of mass production, anotch 111 is provided in the elastic member 103, and the rigidity of theelastic member 103 is lowered, and the spring constant is decreased soas to have a sufficient flexibility.

Besides, torsion and other changes of the carriage and others are alsoknown to have a serious effect on the operation of the head supportdevice, and technologies for decreasing the vibration mode such asdistortion have been proposed (for example, see page 6 of JapanesePatent Laid-open Application No. H8-45214). In such specific proposal,by adjusting the bent shape of the spring section (corresponding to theelastic member), and optimally setting the bump (corresponding to thebending size of the spring section) and offset (corresponding to thedifference in position height between the connecting portion of the loadbeam and spring and the portion of connecting the spring section to thecarriage), the slider is hardly moved despite linear torsional resonancefrequency.

In the head support device of such conventional structure, however,since it is designed to lower the rigidity of the elastic member 103,decrease the spring constant and hence obtain a sufficient flexibilityby providing the notch 111 in the elastic member 103 or forming the loadbeam 102 in a thin plate structure, the resonance frequency declineswhen the head support device 101 moves the magnetic head to a desiredtrack position at high speed, and vibration mode such as torsion occurs,and consequently off-track may occur, it may take a longer time tosettle the vibration mode, and there is a limit for shortening theaccess time.

Besides, if the bump and offset are set optimally by adjusting thebending shape of the spring section, although it is effective for thelinear torsional resonance frequency, enough effect is not obtained forhigher torsional resonance frequency. Optimal setting of the bump andoffset in the spring section requires adjustment in each head supportdevice in consideration of manufacturing fluctuations of distancebetween the head arm (corresponding to the carriage) and the disk, andthis is not an easy operation, and the number of manufacturing processesis increased.

The speed of moving the magnetic head to a desired track position isbecoming faster recently, and hence a very high torsional vibrationfrequency is provided as torsional vibration mode, and the magnetic headmay go off the desired track position owing to the higher torsionalvibration mode.

To make the linear torsional mode of the load beam less obvious, thebending shape of the spring section (elastic member) of the load beam isadjusted. However, when the setting height (Z-height) of the load beamis changed, the characteristic is changed, and extra adjustment isneeded to obtain a stable performance.

It is hence an object of the invention to solve these problems andpresent a head support device which is free from effects ofmanufacturing fluctuations of the distance between the carriage andmagnetic recording medium, heightened in rigidity of load beam to have avery large resonance frequency, free from effects of fluctuations ofsetting height of load beam, stabilized in resonance characteristic,enhanced in the reliability of head positioning control characteristicso as to be free from off-track problem against higher torsionalresonance, small in size and light in weight, and excellent in operationstability, and a disk apparatus having such head support device.

DISCLOSURE OF THE INVENTION

To achieve the object, the head support device of the invention has astructure comprising a head, a load beam for supporting the head, abearing provided between the load beam and a carriage, being rotatablein the perpendicular direction to the recording medium, an elasticmember for coupling the load beam and the carriage, and a sidereinforcement provided in the load beam. It also has a structurecomprising a head, a load beam for supporting the head, a dimpleprovided in the load beam, a bearing provided between the load beam anda carriage, being rotatable in the perpendicular direction to therecording medium, an elastic member for coupling the load beam and thecarriage, and a side reinforcement provided in the load beam. It alsohas a structure comprising a head, a load beam for supporting the head,a bearing provided between the load beam and a carriage, being rotatablein the perpendicular direction to the recording medium, and an elasticmember for coupling the load beam and the carriage, and sidereinforcements provided in the load beam, in which an opening is formedin the load beam. In addition to these structures, it further has astructure in which gimbals is provided between the slider and load beam,a structure in which the bearing is provided in the carriage and thepeak of the bearing contacts with the load beam, a structure in whichthe bearing is provided in the load beam and the peak of the bearingcontacts with the carriage, a structure in which the elastic member isformed integrally with the load beam, a structure in which the bearingis a pair of pivots, a structure in which the bearing is composed of twopivots, a structure further comprising a second bearing rotatable in theradial direction of the recording medium, in which the carriage isrotatable about the second bearing, a structure in which the load beamis rotatable about the bearing, a structure in which the load beam isforced by the elastic member in a direction perpendicular to the surfaceof the slider, a structure having a flexure in which the slider isdisposed at the end of the load beam, and a structure in which theslider is disposed in the gimbals of the flexure.

In these structures, by rotating the load beam by overcoming the elasticforce of the elastic member, the slider can be pressed against thesurface of the recording medium by a desired pressing force, and furtherthe rigidity of the load beam is enhanced by the side reinforcement, andthe vibration characteristic is improved, thereby obtaining the headsupport device having the slider moving freely so as to comply with themotion of the surface of the rotating recording medium.

The head support device of the invention further has a structure inwhich the side reinforcement is provided at both side edges of the loadbeam. It also has a structure in which the side reinforcement is made ofresin. It also has a structure in which the side reinforcement is madeof resin, and is disposed in the load beam by integral forming. It alsohas a structure in which the side reinforcement is formed by bending theboth side edges of the load beam. It also has a structure in which theheight of the side reinforcement is greater than the thickness of theload beam. It also has a structure in which the sectional shape isformed like letter W in the section perpendicular to the central line inthe longitudinal direction of the load beam. It also has a structure inwhich the sectional shape is formed like letter H in the sectionperpendicular to the central line in the longitudinal direction of theload beam. It also has a structure in which the entire sectional shapeis formed like letter H by gluing a member having a nearly pi-shapedsection in the section perpendicular to the central line in thelongitudinal direction of the load beam.

In these structures, since the side reinforcement can be formed by anordinary simple processing method, the rigidity of the load beam can beenhanced without requiring high cost, and the resonance frequency issignificantly increased and the resonance characteristic can bestabilized, thereby obtaining the head support device applicable to highaccess speed without off-track problem despite higher torsionalresonance.

The head support device of the invention moreover has a structure inwhich the bearing is composed of two pivots, and the side reinforcementis formed in a flat plane of the load beam, perpendicular to the linelinking the middle point of the two pivots and the peak of the dimple,with the shearing center of the section of the load beam passing throughthe peak of the dimple coinciding with the peak of the dimple. It alsohas a structure in which the bearing is composed of two pivots, and thedimple provided in the load beam has the peak located on theperpendicular bisector of the line linking the peaks of the both pivots.It also has a structure in which the bearing is composed of two pivots,perpendicular to the centerline in the longitudinal direction of theload beam, and the side reinforcement is formed, with the centroid atthe position of center of gravity of the load beam passing through thepeak of the dimple coinciding with the peak of the dimple provided inthe load beam. It also has a structure in which the centroid at theposition of the center of gravity at a section perpendicular to thecenterline in the longitudinal direction of the load beam is positionedon the plane passing through two pivots and the peak of the dimpleprovided in the load beam, and the side reinforcement is formed at bothside edges of the load beam. It also has a structure in which thecentroid at the position of the center of gravity at a sectionperpendicular to the centerline in the longitudinal direction of theload beam is positioned on the line linking the middle point of the linelinking the peaks of the two pivots and the peak of the dimple providedin the load beam, and the side reinforcement is formed at both sideedges of the load beam.

In these structures, in spite of the impact from outside or torsionalvibration when moving the magnetic head to the target track, therigidity of the load beam is increased and the resonance frequencycharacteristic is enhanced, and the position of the peak of the dimpleis not moved despite higher torsional resonance frequency, and henceoff-track problem is not caused, thereby obtaining the head supportdevice applicable to high access speed.

The head support device of the invention moreover has a structurecomprising a head, a load beam for supporting the head, a dimpleprovided in the load beam, a bearing provided between the load beam anda carriage, and an elastic member for coupling the load beam and thecarriage, in which the load beam has an opening. In addition, it alsohas a structure in which the opening is provided in the center of theload beam, a structure in which the opening is formed symmetrically tothe centerline of the load beam, a structure in which the opening isformed in a circular form, elliptical form, or polygonal form, astructure in which the opening is formed in a slit shape, a structure inwhich the end portion of the opening is provided closely to the sidereinforcement, and a structure in which at least two openings areprovided, and each opening is formed at a symmetrical position to thecenterline of the load beam.

In these structures, by rotating the load beam by overcoming the elasticforce of the elastic member made of spring or the like, the slider canbe pressed against the surface of the recording medium by a desiredpressing force, and further the slider can be moved freely along themotion of the surface of the rotating recording medium, the weight andsize are reduced by forming the opening in the side surface, and therebythe head support device capable of adjusting the resonancecharacteristic of the load beam from other side can be obtained.

Moreover, the head support device of the invention moreover has astructure in which the bearing is composed of two pivots, and a balanceris provided in the load beam so that the direction of action of totalcenter of gravity in the direction of the recording medium of theflexure having the slider, rotating parts of the load beam and thebalancer may pass the axis of rotation linking each peak of the pivots.In this structure, without receiving effects of impact force fromoutside, a head support device of high reliability without damage ofslider and magnetic recording medium due to collision can be realized.

The disk apparatus of the invention has a structure comprising arecording medium, a head, a load beam for supporting the head, a bearingprovided between the load beam and a carriage, being rotatable in theperpendicular direction to the recording medium, an elastic member forcoupling the load beam and the carriage, and a side reinforcementprovided in the load beam. It also has a structure comprising arecording medium, a head, a load beam for supporting the head, a dimpleprovided in the load beam, a bearing provided between the load beam anda carriage, being rotatable in the perpendicular direction to therecording medium, and an elastic member for coupling the load beam andthe carriage, in which an opening is provided in the load beam. Inaddition to these structures, it also has a structure in which gimbalsis provided between the slider and load beam, a structure in which thebearing is provided in the carriage and the peak of the bearing contactswith the load beam, a structure in which the bearing is provided in theload beam and the peak of the bearing contacts with the carriage, astructure in which the elastic member is formed integrally with the loadbeam, a structure in which the bearing is a pair of pivots, a structurein which the bearing is composed of two pivots, a structure furthercomprising a second bearing rotatable in the radial direction of therecording medium, in which the carriage is rotatable about the secondbearing, a structure in which the load beam is rotatable about thebearing, and a structure in which the load beam is forced by the elasticmember in a direction perpendicular to the surface of the slider.

In these structures, the head can be moved to a desired track positionat high speed, and the disk apparatus of high reliability substantiallyshortened in the access time can be realized.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a side view showing part of head support device of diskapparatus in preferred embodiment 1 of the invention.

FIG. 2( a) is a perspective view of essential parts showing a schematicstructure of head support device in preferred embodiment 1 of theinvention.

FIG. 2( b) is a perspective exploded view of essential parts showing aschematic structure of head support device in preferred embodiment 1 ofthe invention.

FIG. 3 is a partially cut-away side view of head support device inpreferred embodiment 1 of the invention.

FIG. 4 is a sectional view of load beam showing a plan section passingthe peak of dimple in head support device in preferred embodiment 1 ofthe invention.

FIG. 5 is a perspective view showing other example of load beam in headsupport device in preferred embodiment 1 of the invention.

FIG. 6 is a plan view showing an example of shape and configuration ofopening provided in the plane of the load beam in head support device inpreferred embodiment 1 of the invention.

FIG. 7 is a perspective view showing a structure of disk apparatushaving the head support device in preferred embodiment 1 of theinvention.

FIG. 8 is a partially cut-away side view of head support device inpreferred embodiment 2 of the invention.

FIG. 9 is a perspective view of load beam as seen from the slidermounting side of head support device in preferred embodiment 2 of theinvention.

FIG. 10( a) is a cut-away side view of essential parts of head supportdevice in preferred embodiment 3 of the invention.

FIG. 10( b) is a partially magnified side view of essential parts ofhead support device in FIG. 10( a).

FIG. 11 is a side view showing part of head support device and disk ofdisk apparatus in preferred embodiment 4 of the invention.

FIG. 12( a) is a perspective view of essential parts showing a schematicstructure of head support device in preferred embodiment 4 of theinvention.

FIG. 12( b) is a perspective exploded view of essential parts showing aschematic structure of head support device in preferred embodiment 4 ofthe invention.

FIG. 13 is a cut-away side view of essential parts of head supportdevice in preferred embodiment 4 of the invention.

FIG. 14 is a sectional view of load beam cut off at a plane passingthrough the dimple peak of head support device in preferred embodiment 4of the invention.

FIG. 15 is a cut-away side view of essential parts of other head supportdevice in preferred embodiment 4 of the invention.

FIG. 16 is a perspective view of load beam as seen from the slidermounting side of other head support device in preferred embodiment 4 ofthe invention.

FIG. 17( a) is a perspective view of essential parts showing a schematicstructure of head support device in preferred embodiment 5 of theinvention.

FIG. 17( b) is a perspective exploded view of essential parts showing aschematic structure of head support device in preferred embodiment 5 ofthe invention.

FIG. 18 is a sectional view of load beam cut off at a plane passingthrough the dimple peak of head support device in preferred embodiment 5of the invention.

FIG. 19 is a plan view showing structure of essential parts of aconventional magnetic recording and reproducing apparatus.

FIG. 20 is a perspective view of essential parts for explaining thestructure and action of a conventional head support device.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

Preferred preferred embodiments of the invention are described belowwhile referring to the accompanying drawings.

Preferred Embodiment 1

FIG. 1, FIG. 2 and FIG. 3 are drawings for explaining the head supportdevice of disk apparatus in preferred embodiment 1 of the invention. Amagnetic recording and reproducing apparatus is explained below as anexample of disk apparatus. FIG. 1 is a side view showing the headsupport device having a floating type head of disk apparatus used incomputer storage or the like together with part of disk such as magneticrecording medium. FIG. 2( a) is a perspective view of essential partsshowing a schematic structure of head support device of the invention,and FIG. 2( b) is a perspective exploded view of essential parts showinga schematic structure of head support device of the invention. FIG. 3 isa partially cut-away side view of essential parts of head support deviceof the invention.

In FIG. 1, to be opposite to magnetic recording medium layers formed onboth upper and lower sides of a plurality of magnetic recording media 1,magnetic heads (not shown) mounted on a slider 3 of a plurality of headsupport devices 2 are composed. At the time of recording or reproductionof the magnetic recording and reproducing apparatus, by the action ofdriving means such as voice coil, provided in the carriage 4, themagnetic head mounted on the slider 3 is rotated about the center ofrotation of a second bearing 6 in the radial direction of the magneticrecording medium 1, and is positioned at a desired track of the magneticrecording medium 1. As the driving means 5, a voice coil motor is used,but it is not limited to voice coil motor, but linear motor or otherdriving means may be employed. In the following explanation, as shown inFIG. 3, the head support device 2 disposed to be opposite to the lowerside of the magnetic recording medium 1 is described.

In FIG. 1, two magnetic recording media 1 are shown, but the sameeffects are obtained by using one magnetic recording medium or three ormore magnetic recording media. In the explanation, both upper and lowersides of the magnetic recording media are used, but the same effects areobtained by a structure having one head support device corresponding toone side of the magnetic recording medium only. In FIG. 2 and FIG. 3,the slider 3 mounting a magnetic head (not shown) at one end isdisposed, an elastic member 23 such as plate spring is formed in part ofa load beam 22 to which a flexure 21 having gimbals 20 integrallyforming a thin metal plate such as SUS and a flexible wiring board isadhered, and an open end of the elastic member 23 is affixed to acarriage 4 by known method such as spot welding method, ultrasonicwelding method, or laser welding method. The elastic member 23 may becomposed of a different elastic member from the load beam 22, and when adifferent elastic member is used, one end of the elastic member isaffixed to the load beam 22 and the other end to the carriage 4 bysimilar known welding method. The carriage 4 has a pair of (two) pivots25 provided at right and left symmetrical positions of a centerline 24in the longitudinal direction of the load beam 22 (by the pivots 25, theload beam 22 can be rotated in a direction perpendicular to the magneticrecording medium 1). Therefore, by overcoming the elastic force of theelastic member 23 such as plate spring of the load beam 22 affixed tothe carriage 4, the rotary portion (the portion excluding the elasticmember 23) of the load beam 22 is pushed up so as to rotate in thedirection of arrow A in FIG. 3 about the two pivots 25, and the slider 3disposed on the load beam 22 is forced to the side of the magneticrecording medium 1 so that the slider 3 may press the surface of themagnetic recording medium 1 (not shown in FIG. 2). A balancer 26 (notshown in FIG. 2) is affixed to the other end of the load beam 22 (theend of the opposite side of the slider 3 side), and the total center ofgravity in the direction of the magnetic recording medium 1 of therotary portion of the load beam 22, the flexure 21 having the slider 3and the balancer 26 is linked to the peaks of the two pivots 25 of thecarriage 4, and this linking line is the axis of rotation, and it isformed on a plane perpendicular to the magnetic recording medium 1including this axis of rotation. By using such balancer 26, if receivingan impulse force by impact from outside or the like, there is no forceacting to rotate the load beam 22 about the axis of rotation linking thepeaks of the two pivots 25 of the carriage 4, and hence the slider 3does not collide against and damage the surface of the magneticrecording medium 1, so that the reliability may be enhanced.

On the surface facing the slider 3 of the load beam 22, further, thereis a dimple 28 having a peak 27 on a face perpendicular to the plane 22a of the load beam 22 including the centerline 24 in its longitudinaldirection, and at the peak 27, the load beam 22 oscillatably supportingthe slider 3 is connected by way of the flexure 21. By the peak 27 ofthe dimple 28, the load beam 22 and the slider 3 contact with each otherdirectly or by way of the flexure 21, and the slider 3 can move freelyalong the rotating motion of the surface of the magnetic recordingmedium 1. The centerline 24 in the longitudinal direction of the loadbeam 22 is set so as to pass through the center of rotation rotated bythe action of the voice coil (not shown) as the driving means having theload beam 22 provided on the carriage 4 or the like. The peak 27 of thedimple 28 may be designed to contact with the slider 3 directly, insteadof supporting the slider 3 by way of the flexure 21.

FIG. 4 is a sectional view of load beam 22 seen on a sectionperpendicular to the centerline 24 in FIG. 2( a) and at a plane passingthrough the peak 27 of the dimple 28. As shown in FIG. 4, a sidereinforcement 41 is formed almost on the whole surface at the right andleft sides of the load beam 22. In FIG. 4, a V-section is formed atright and left sides of the load beam 22, and the side reinforcement 41is shown in a W-section on the whole. Not limited to the W-section, theside reinforcement 41 may be formed in any other shape, but it isdesired to be shaped by bending process. Or other member may be formedintegrally. Instead of forming on the entire surface, the sidereinforcement 41 may be formed in part, in the portion up to theopposite side periphery of the end portion of the slider 3 side of theelastic member 23 of plate spring or the like at least from the slider 3side end portion.

Since the side reinforcement 41 is also present near the elastic member23 of plate spring or the like, the rigidity of the load beam 22 isincreased, and vertical swing in the direction of the magnetic recordingmedium 1 of the load beam 22 due to impact or vibration, lateral swingalong the surface of the magnetic recording medium 1, or swing due totorsion can be suppressed, and the load beam 22 can be composed of athin plate, so that lighter weight and smaller size may be realized.

Besides, by forming the side reinforcement 41, the rigidity of the loadbeam 22 is increased substantially, and therefore as shown in aperspective view of schematic structure of the essential parts of thehead support device in FIG. 2( a), an opening 29 composed of a pluralityof holes may be provided in the plane 22 a of the load beam 22, or asshown in FIG. 5, an opening 51 of a hole in the longitudinal directionmay be provided in the center of the plane 22 a of the load beam 22,thereby reducing the weight, and further the resonance characteristic ofthe load beam 22 can be adjusted. FIG. 2( a) shows an example ofdisposing the opening 29 along the centerline 24 by forming threecircles different in diameter in the plane 22 a of the load beam 22, butthe opening 29 formed in the load beam 22 composing the head supportdevice in preferred embodiment 1 of the invention is not limited to thisstructure alone. The opening 29 may be formed in elliptical or polygonalshape instead of circular shape, or a plurality of different shapes,instead of same shape, may be combined. The size of the opening 29 canbe set freely so as to be formed in the plane 22 a of the load beam 22,and the end portion of the opening 29 may be provided near the sidereinforcement 41. Further, the opening 29 may be formed in a fine louvershape, and the load beam 22 may be formed therein. However, the opening29 is preferred to be formed in a symmetrical shape or symmetricalconfiguration to the centerline 24 of the load beam 22.

Thus, by disposing the opening 29 in the plane 22 a of the load beam 22,the load beam 22 can be reduced in weight and size same as in the caseof composition of a thin plate. Further, in the load beam 22 made ofthin plate, the opening 29 can be also provided in the plane 22 a of theload beam 22. The shape, number, and configuration of the openings 29and the plate thickness of the load beam 22 may be properly selected incombination in consideration of the rigidity of the load beam 22. FIG. 6is a plan view of a typical example of opening formed in the load beam.

When the head support device 2 moves the magnetic head to a desiredtrack position at high speed, as the speed is higher, torsionalvibration is more likely to occur in the load beam 22. At this time, iftorsional vibration occurs in the load beam 22, as far as the relativepositions of the slider 3 and the peak 27 of the dimple 28 of the loadbeam 22 contacting therewith are invariable, off-track trouble does notoccur due to the torsional vibration when moving the magnetic head tothe desired track position at high speed, and the access time to thedesired track position can be shortened. To realize such configuration,the position of the peak 27 of the dimple 28 of the load beam 22 isrequired to coincide with the neutral axis of torsion of the load beam22.

At this time, as far as the shape of the section of the load beam 22 cutoff by a plane perpendicular to the centerline 24 in FIG. 2( a) andpassing through the peak 27 of the dimple 28 is symmetrical to thecenterline 24 both vertically and laterally, it is present on the planepassing three points, that is, the peaks of two pivots 25 of thecarriage 4 and the peak 27 of the dimple 28 of the load beam 22, and aline 31 (see FIG. 3) at right angle to the line linking the peaks of thetwo pivots 25 and passing the middle point coincides with the neutralaxis of torsion of the load beam 22. For this purpose, the shape of theside reinforcement 41 in the individual portions of the load beam 22should be set so that the centroid of the section of the load beam 22shown ion FIG. 4 and the section of the load beam 22 parallel to thissection may be present on the line 31. In other words, when the shape ofthe section of the load beam 22 is symmetrical to the centerline 24 bothvertically and laterally, in the event of torsional resonance of theload beam 22, it is enough to consider the stress due to torsionalmoment only, and it is enough to match the centroid at the positionwhere the stress is zero and the position of the peak 27 of the dimple28 of the load beam 22.

In the load beam 22 of the head support device in preferred embodiment 1of the invention, however, on the plane perpendicular to the centerline24 in FIG. 2( a) and passing the peak 27 of the dimple 28, as shown in asectional view in FIG. 4, the load beam 22 has the side reinforcement 41in a V-section at right and left sides and a W-section on the whole.This load beam 22 is symmetrical to the centerline 24 laterally, but isnot symmetrical in the vertical direction, and therefore the position ofthe peak 27 of the dimple 28 cannot be discussed in terms of thecentroid at the section of the load beam 22.

In this case, lacking symmetry in the vertical direction, the positionwhere the combined stress of the shearing stresses caused by torsionalvibration is zero must be matched with the position of the peak 27 ofthe dimple 28 of the load beam 22, and this position must be matchedwith the neutral axis of torsion of the load beam 22.

Such point of zero combined stress of shearing stresses due to torsionalvibration is called the center of shearing in the field of mechanicalengineering. Therefore, if not symmetrical on the plane perpendicular tothe centerline 24 of the load beam 22 and passing the peak 27 of thedimple 28 in a sectional view, by matching the position of the peak 27of the dimple 28 with the center of shearing, it coincides with theneutral axis of torsion of the load beam 22, and hence when moving themagnetic head to the desired track position at a high speed, therelative positions of the slider 3 and the peak 27 of the dimple 28 ofthe load beam 22 contacting therewith are invariable, and off-track doesnot occur due to torsional vibration.

Therefore, in the case of the load beam 22 symmetrical laterally but notsymmetrical vertically, having the side reinforcement 41 formed inV-section on right and left side and W-section on the whole, the shapeof the side reinforcement 41 in each portion of the load beam 22 shouldbe set so that the center of shearing of the section of the load beam 22shown in FIG. 4 and the section of the load beam 22 parallel to thissection may be present on the plane passing three points, that is, thepeaks of two pivots 25 of the carriage 4 and the peak 27 of the dimple28 of the load beam 22, and on the line 31 at right angle to the linelinking the peaks of the two pivots 25 and passing the middle point.Accordingly, the peak 27 of the dimple 28 coincides with the neutralaxis of torsion of the load beam 22.

In the load beam 22 having thus designed side reinforcement 41, sincethe peak 27 of the dimple 28 coincides with the neutral axis of torsionof the load beam 22, if the peak 27 of the dimple 28 of the load beam 22is subject to torsional vibration as indicated by broken line in FIG. 4,the slider 3 having the magnetic head is not moved, and off-track doesnot occur if the magnetic head is moved to the desired track position athigh speed, so that the access time to the desired track position can beshortened.

Instead of setting the shape of the side reinforcement 41 in allportions of the load beam 22 so that the center of shearing of allsections of the load beam 22 may be located on the line 31, by settingthe shape of the side reinforcement 41 so that the center of shearing ofeach section near the dimple 28 of the loading beam 22 may be located onthe line 31, and that the center of shearing of each section may begradually departed from the line 31 as being going apart from thevicinity of the dimple 28 of the load beam 22 toward the elastic member23 of the load beam 22, the off-track amount by torsional vibration isvery small, and there is no practical problem, and thereby the accesstime to the desired track position can be shortened.

In the explanation of the head support device 2 in preferred embodiment1 of the invention, the load beam 22 has the side reinforcement 41having a V-section at right and left sides of the load beam 22, and aW-section on the whole, and it is symmetrical laterally but notsymmetrical vertically, and the dimple 28 having the peak 27 is formedin the plane perpendicular to the plane 22 a of the load beam 22including the centerline 24 in its longitudinal direction, and theposition of the peak 27 coincides on the perpendicular bisector of theline linking the peaks of the both pivots 25 at the neutral axis (line31) of torsion, but the invention is not limited to this example alone,and the position of the peak 27 of the dimple 28 may be anywhere capableof forming the dimple 28 on the plane 22 a of the load beam 22, and maybe set at any position coinciding with the section of the load beam 22and the center of shearing of each section parallel to the section. Atthis time, the neutral position of torsion is present on a plane passingthe peaks of the two pivots 25 and the peak 27 of the dimple 28, andcoincides with the line 31 passing the middle point linking the peaks ofthe two pivots 25 and the peak 27 of the dimple 28. Further, the line 31is not required to be a straight line, but may be a moderate curve. Inthis case, needless to say, at least the section of the load beam 22 isnot symmetrical to the centerline 24 in its longitudinal direction. Atthis time, however, the center of shearing of the section of the loadbeam 22 and each section parallel to this section is present on theplane passing three points, that is, the peaks of two pivots 25 of thecarriage 4 and the peak 27 of the dimple 28 of the load beam 22, and onthe line 31 passing the middle point of the line linking the peaks ofthe two pivots 25, but the line 31 is not perpendicular bisector linkingthe peaks of the two pivots 25. In this case, too, the peak 27 of thedimple 28 can be matched with the neutral axis of torsion of the loadbeam 22.

Moreover, by the side reinforcement 41, the rigidity of the load beam 22is substantially increased, and further by matching the position of thepeak 27 of the dimple 28 of the load beam 22 with the neutral axis oftorsion of the load beam 22, if fluctuation occurs in the distancebetween the carriage 4 and magnetic recording medium 1, that is, in thesetting height of the load beam 22 due to manufacturing fluctuations,the resonance characteristic of the load beam 22 can be stabilized andhigher resonance of torsion can be decreased in spite of impact,vibration, or vibration due to seek action of moving the magnetic headto the desired track, so that off-track occurs hardly, in other words,effects of fluctuations of setting height of the load beam 22 can beeliminated.

The head support device 2 having such configuration can be applied,needless to say, in all head support devices including the head supportdevice opposite to the upper side of the magnetic recording medium 1,and moreover, as shown in FIG. 7, by applying in a magnetic recordingand reproducing apparatus 65 having a head support device 64 rotated inthe radial direction by the action of a voice coil 63, on a magneticrecording medium 62 rotated and driven by a spindle motor 61, themagnetic head can be moved to a desired track position at high speed,and the magnetic recording and reproducing apparatus 65 substantiallyshortened in the access time is realized.

Thus, according to preferred embodiment 1, if the setting height of theload beam fluctuates, the resonance characteristic of the load beam canbe stabilized, and the position of the slider is not changed in spite oftorsional vibration, and the head positioning control characteristic isimproved, and also the access time of moving the magnetic head to thedesired track can be shortened.

Still more, by reinforcing the rigidity of the load beam by composingthe side reinforcement along the elastic member composed of platespring, an opening made of holes can be provided in the load beam, orthe load beam can be made of a thin plate, so that the head supportdevice reduced in weight and size can be realized.

By mounting such head support device, a disk apparatus enhanced in thehead positioning control characteristic, capable of moving the magnetichead to the desired track position at high speed, and significantlyshortened in the access time can be realized.

In the above explanation, the peak of the pivot 25 is a point, but notlimited to a point, the load beam may be rotated by forming in wedgeform or other axial line.

Preferred Embodiment 2

FIG. 8 and FIG. 9 are diagrams explaining the head support device inpreferred embodiment 2 of the invention, and FIG. 8 is a sectional viewshowing essential parts of the head support device in a cut-away view,and FIG. 9 is a perspective view of load beam as seen from the slidermounting side. In FIG. 8 and FIG. 9, same constituent elements as inpreferred embodiment 1 shown in FIG. 2( a) and FIG. 3 are identifiedwith same reference numerals as in FIG. 2( a) and FIG. 3. Same as inpreferred embodiment 1, the magnetic recording and reproducing apparatusis explained as the disk apparatus. What preferred embodiment 2 differsfrom preferred embodiment 1 is that two pivots are not formed in thecarriage, but are formed at right and left symmetrical positions acrossthe centerline in the longitudinal direction of the load beam.

In FIG. 8 and FIG. 9, an elastic member 23 made of plate spring or thelike is formed in part of a load beam 22 having a flexure 21 disposing aslider 3 mounting a magnetic head (not shown) affixed at one end, andthe open end of the elastic member 23 is affixed to a carriage 4 in aknown method same as in preferred embodiment 1. The elastic member 23may be made of a separate member from the load beam 22 same as inpreferred embodiment 1. Two pivots 25 are provided in the load beam 22at right and left symmetrical positions across the centerline 24 in itslongitudinal direction, and the slider 3 disposed in the load beam 22pushes up the load beam 22 by pressing the surface of a magneticrecording medium 1 by overcoming the elastic force of the elastic member23 of the load beam 22 affixed to the carriage 4, thereby forcing theslider 3 to the side of the magnetic recording medium 1.

Further, same as in preferred embodiment 1, a dimple 28 is formed on thesurface facing the slider 3 of the load beam 22, and the slider 3 isconnected to the load beam 22 so that it may contact with the slider 3by way of a flexure 21 at a peak 27 of the dimples 28. The centerline 24in the longitudinal direction of the load beam 22 is, same as inpreferred embodiment 1, set to pass the center of rotation rotated bythe action of a voice coil (not shown). The peak 27 of the dimple 28 ispresent on a plane passing three points, that is, the peaks of the twopivots 25 of the load beam 22 and the peak 27 of the dimple 28, and on aline 31 passing the middle of the line linking the peaks of the twopivots 25 and at right angle to the line linking the peaks of the twopivots 25, and the line 31 coincides with the neutral axis of torsion ofthe load beam 22. Accordingly, the shape of a side reinforcement 71 ineach portion of the load beam 22 is determined so that the center ofshearing of each section of the load beam 22 or the centroid may belocated on the line 31.

Therefore, the head support device composed of the load beam 22 havingsuch shape has the same effects as in preferred embodiment 1. That is,the peak 27 of the dimple 28 of the load beam 22 is not moved iftorsional vibration occurs, and off-track does not occur if the magnetichead is moved to a desired track position at high speed, and the accesstime to the desired track position can be shortened, and furtherfluctuations of setting height of the load beam 22 due to manufacturingfluctuations are eliminated, and the resonance characteristic of theload beam 22 is stabilized in spite of impact, vibration or vibration byseek action for moving the magnetic head to the desired track, andhigher resonance of torsion can be decreased, too. Moreover, byproviding an opening forming holes, for example, in the middle of theplane 22 a of the load beam 22, the weight may be reduced and theresonance characteristic of the load beam 22 can be adjusted at the sametime, or by forming the load beam 22 by a thin plate, the weight andsize can be reduced.

By applying the head support device having such structure, the head canbe moved to a desired track position at high speed, and an excellentdisk apparatus significantly shortened in the access time is realized.

Thus, according to preferred embodiment 2, having the same effects as inpreferred embodiment 1, the resonance characteristic of the load beamcan be stabilized if the setting height of the load beam fluctuates, theslider position is not changed despite torsional vibration, the headpositioning control characteristic is enhanced, and the access time formoving the magnetic head to a desired track can be shortened.

Further, by forming holes in part of the load beam, or providing anopening by forming holes, or forming the load beam by using a thinplate, a head support device reduced in weight and size can be realized.

FIG. 9 shows an example of an opening 51 made of a hole in thelongitudinal direction provided in the middle of the plane 22 a of theload beam 22, but the shape and configuration of the opening is notlimited to this example, and various shapes and configuration shown inFIG. 6 may be simiarly employed as in preferred embodiment 1.

In the explanation of the head support device in preferred embodiment 2of the invention, same as in preferred embodiment 1, the load beam 22has the side reinforcement 71 having a V-section at right and leftsides, and a W-section on the whole, and it is symmetrical laterally butnot symmetrical vertically, and the dimple 28 having the peak 27 isformed in the plane perpendicular to the plane 22 a of the load beam 22including the centerline 24 in its longitudinal direction, and theposition of the peak 27 coincides on the perpendicular bisector of theline linking the peaks of the both pivots 25 at the neutral axis (line31) of torsion, but the head support device in preferred embodiment 2 ofthe invention is not limited to this example alone, and the position ofthe peak 27 of the dimple 28 may be anywhere as far as the dimple 28 isformed on the plane 22 a of the load beam 22, and it may be set at anyposition coinciding with the section of the load beam 22 and the centerof shearing of each section parallel to the section. At this time, theneutral position of torsion is present on a plane passing the peaks ofthe two pivots 25 and the peak 27 of the dimple 28, and coincides withthe line 31 passing the middle point linking the peaks of the two pivots25 and the peak 27 of the dimple 28. Further, the line 31 is notrequired to be a straight line, but may be a moderate curve. In thiscase, needless to say, at least the section of the load beam 22 is notsymmetrical to the centerline 24 in its longitudinal direction. At thistime, however, the center of shearing of the section of the load beam 22and each section parallel to this section is present on the planepassing three points, that is, the peaks of two pivots 25 of thecarriage 4 and the peak 27 of the dimple 28 of the load beam 22, and onthe line 31 passing the middle point of the line linking the peaks ofthe two pivots 25, but the line 31 is not perpendicular bisector linkingthe peaks of the two pivots 25, but the peak 27 of the dimple 28 can bematched with the neutral axis of torsion of the load beam 22.

By mounting such head support device, further, the disk apparatus isenhanced in the head positioning control characteristic, capable ofmoving the magnetic head to a desired track position at high speed, andsubstantially shortened in the access time.

Preferred Embodiment 3

FIG. 10 is a diagram explaining the head support device in preferredembodiment 3 of the invention, and FIG. 10( a) is a side view showingessential parts of the head support device in a cut-away view, and FIG.10( b) is a partially magnified side view of FIG. 10( a). In FIG. 10,same constituent elements as in preferred embodiment 1 shown in FIG. 2(a) and FIG. 3 are identified with same reference numerals as in FIG. 2(a) and FIG. 3. Same as in preferred embodiment 1, the magnetic recordingand reproducing apparatus is explained as the disk apparatus. Whatpreferred embodiment 3 differs from preferred embodiment 1 is that thedimple is not formed in the load beam contacting with the gimbals of theflexure mounting the slider, but is formed in the gimbals of the flexuremounting the slider.

In FIG. 10, different from preferred embodiment 1 shown in FIG. 2( a),FIG. 3, and FIG. 4, the dimple 28 is not formed in the load beam 22, butthe dimple 28 is formed in the flexure 21 mounting the slider 3, and thepeak 27 of the dimple 28 contacts with: the surface of the slider 3 sideof the load beam 22. The carriage 4, load beam 22, and slider 3 aredisposed so that the peak 27 of the dimple 28 of the slider 3 may comeon the perpendicular bisector of the line linking the peaks of the twopivots 25 of the carriage 4. The other configuration is same as inpreferred embodiment 1 and preferred embodiment 2, and the detaileddescription is omitted herein.

In this head support device, same as in preferred embodiment 1, theshape of the side reinforcement in each portion of the load beam 22 isdetermined so that the neutral axis of torsion of the load beam 22, thatis, the center of shearing at the section in each portion of the loadbeam 22, or the centroid may be present on a plane including the peaksof the two pivots 25 of the carriage 4 and the peak 27 of the dimple 28of the slider 3, and on a line 31 passing the middle of the line linkingthe peaks of the two pivots 25 of the carriage 4. Herein, since theplate thickness of the plane 22 a of the load beam 22 is very thin, theperpendicular bisector of the line present on the plane including thepeaks of the two pivots 25 of the carriage 4 and the peak 27 of thedimple 28 of the slider 3, and linking the peaks of the two pivots 25 ofthe carriage 4 nearly coincides with the centerline in the longitudinaldirection of the load beam 22.

Therefore, the head support device having such configuration and thedisk apparatus comprising such head support device have the same effectsas in the foregoing preferred embodiment 1 and preferred embodiment, andexplanation of the effects is omitted to avoid duplication.

In preferred embodiment 3, the two pivots 25 may be also provided in theload beam 22 same as in preferred embodiment 2, but its specificdescription is omitted.

In the explanation of the head support device in preferred embodiment 3of the invention, same as in preferred embodiment 1 and preferredembodiment 2, the load beam 22 has the side reinforcement 41 having aV-section at right and left sides, and a W-section on the whole, and itis symmetrical laterally but not symmetrical vertically, and the dimple28 having the peak 27 is formed in the plane perpendicular to the plane22 a of the load beam 22 including the centerline 24 in its longitudinaldirection, and the position of the peak 27 coincides on theperpendicular bisector of the line linking the peaks of the both pivots25 at the neutral axis (line 31) of torsion, but the head support devicein preferred embodiment 3 of the invention is not limited to thisexample alone, and the position of the peak 27 of the dimple 28 may beanywhere as far as the dimple 28 is formed on the plane 22 a of the loadbeam 22, and it may be set at any position coinciding with the sectionof the load beam 22 and the center of shearing of each section parallelto the section. In such configuration, the same effects are obtained.

In the load beam 22 of the head support device in preferred embodiment 3of the invention, too, an opening may be formed in the plane of the loadbeam 22, and the weight and size can be reduced, and also the resonancecharacteristic of the load beam 22 can be adjusted. The shape andconfiguration of the opening may be same as explained in preferredembodiment 1.

According to preferred embodiment 3, same effects as in preferredembodiment 1 and preferred embodiment 2 are obtained, and if the settingheight of the load beam fluctuates, the resonance characteristic of theload beam may be stabilized, and the slider position is not changed bytorsional vibration, and the head positioning control characteristic isenhanced, and the access time of moving the magnetic head to a desiredtrack can be shortened.

Besides, the opening made of holes may be formed, for example, in partof the load beam or the load beam may be formed by using a thin plate,and therefore the head support device reduced in weight and size can berealized.

By mounting such head support device, further, the disk apparatus isenhanced in the head positioning control characteristic, capable ofmoving the magnetic head to a desired track position at high speed, andsubstantially shortened in the access time.

Preferred Embodiment 4

FIG. 11, FIG. 12, and FIG. 13 are diagrams explaining the head supportdevice of a disk apparatus in preferred embodiment 4 of the invention.FIG. 11 is a side view showing the head support device of the diskapparatus in preferred embodiment 4 together with part of the disk suchas magnetic recording medium. FIG. 12( a) is a perspective view ofessential parts showing a schematic structure of the head support deviceof preferred embodiment 4, and FIG. 12( b) is a perspective explodedview of essential parts showing a schematic structure of the headsupport device of preferred embodiment 4. FIG. 13 is a partiallycut-away side view of essential parts of the head support device inpreferred embodiment 4. FIG. 11, FIG. 12, and FIG. 13 correspond to FIG.1, FIG. 2, and FIG. 3 of preferred embodiment 1, respectively, and sameconstituent elements as in FIG. 1, FIG. 2, and FIG. 3 are identifiedwith same reference numerals. Same as in preferred embodiment 1, themagnetic recording and reproducing apparatus is explained as the diskapparatus, but to avoid duplication of similar explanation as inpreferred embodiment 1, mainly different points are described below.

As shown in FIG. 11 and FIG. 12, the head support device 2 in preferredembodiment 4 of the invention has a slider 3 mounting a magnetic head(not shown) at one end, and a flexure 21 having gimbals 20 integrallyforming a thin metal plate of SUS or the like and a flexible wiringboard is affixed to a load beam 22, of which one part has an elasticmember 23 made of plate spring or the like, and the open end of theelastic member 23 is affixed to a carriage 4 by known method such asspot welding method, ultrasonic welding method, or laser welding method.The elastic member 23 may be also made of a different member from theload beam 22. The carriage 4 has two pivots 25 disposed at right ad leftsymmetrical positions across the centerline in its longitudinaldirection. Therefore, by overcoming the elastic force of the elasticmember 23 of the load beam 22 affixed to the carriage 4, the rotaryportion (the portion excluding the elastic member 23) of the load beam22 is pushed up so as to rotate in the direction of arrow A in FIG. 13about the two pivots 25, and the slider 3 disposed on the load beam 22is forced to the side of the magnetic recording medium 1 so that theslider 3 may press the surface of the magnetic recording medium 1. Abalancer 26 is affixed to the end of the load beam 22 at the oppositeside of the slider 3 side, and the total center of gravity in thedirection of the magnetic recording medium 1 of the rotary portion ofthe load beam 22, the flexure 21 having the slider 3 and the balancer 26is located on the line linking the peaks of the two pivots 25 of thecarriage 4, and this line is the axis of rotation, and it is composed tobe present on a plane perpendicular to the magnetic recording medium 1including this axis of rotation. Hence, if receiving an impact or thelike from outside, there is no force acting to rotate the load beam 22about the axis of rotation linking the peaks of the two pivots 25 of thecarriage 4, and hence the slider 3 does not collide against and damagethe surface of the magnetic recording medium 1.

On the surface facing the slider 3 of the load beam 22, further, thereis a dimple 28 having a peak 27 on a face perpendicular to the plane 22a of the load beam 22 including the centerline 24 in its longitudinaldirection, and at the peak 27, the load beam 22 oscillatably supportingthe slider 3 is connected by way of the flexure 21. By the peak 27 ofthe dimple 28, the load beam 22 and the slider 3 contact with each otherdirectly or by way of the flexure 21, and the slider 3 can move freelyalong the rotating motion of the surface of the magnetic recordingmedium 1. The centerline 24 in the longitudinal direction of the loadbeam 22 is set so as to pass through the center of rotation rotated bythe action of the voice coil (not shown) provided on the carriage 4 orthe like. The peak 27 of the dimple 28 may be designed to contact withthe slider 3 directly, instead of supporting the slider 3 by way of theflexure 21.

These configurations are same as in preferred embodiment 1. However, thehead support device 2 of the disk apparatus in preferred embodiment 4 ofthe invention differs from preferred embodiment 1 in the structure ofthe load beam 22 and flexure 21. As clear from FIG. 14 given as asectional view cut off by a plane perpendicular to the centerline 24 inFIGS. 12( a) and (b) and passing the peak 27 of the dimple 28, the loadbeam 22 and the flexure 21 of the head support device 2 in preferredembodiment 4 of the invention have side reinforcements 41 a, 41 b formedon almost entire surface of both right and left sides, and the structurehas a pi-section. Both outer sides of principal parts, not the pi-shapedside reinforcements 41 a, 41 b of the load beams 22 and flexure 21, aremutually affixed to contact with each other, and an entire structure ofH-section is formed.

The side reinforcements 41 a, 41 b formed in pi-section at both sides ofthe load beam 22 and flexure 21 may be formed either by bending processor by integrally forming other member. Instead of forming the sidereinforcements 41 a, 41 b on the entire side surfaces, they may beformed only in a peripheral area of the opposite side of the slider 3side end portion of the elastic member 23 at least from the slider 3side end portion. By forming such side reinforcements 41 a, 41 b, therigidity of the load beam 22 becomes very high, and as shown in aperspective view of schematic structure of essential parts of the headsupport device in FIG. 12( a), and therefore a plurality of openings 29may be formed in the plane 22 a of the load beam 22, or an opening 51made of a hole in the longitudinal direction may be provided in themiddle of the plane 22 a of the load beam 22 as shown in FIG. 5, so thatthe weight may be reduced, and also the resonance characteristic of theload beam 22 may be adjusted. Also, near the elastic member 23, sincethe side reinforcements 41 a, 41 b are provided, the rigidity of theload beam 22 is increased, and it is effective to suppress verticalswing of the load beam 22 in the direction of the magnetic recordingmedium 1 side due to impact or vibration, lateral swing along thesurface of the magnetic recording medium 1, or swing due to torsion, andthe load beam 22 may be formed of a thin plate, thereby reducing inweight and size.

Examples of shape and configuration of the openings 29, 51 provided inthe plane 22 a of the load beam 22 include the opening 29 made of aplurality of holes provided in the plane 22 a of the load beam 22 inFIG. 12( a) and the opening 51 made of a hole in the longitudinaldirection provided in the middle of the plane 22 a of the load beam 22in FIG. 5, but the shape and configuration of the openings 29, 51 arenot limited to these examples alone, but various shapes andconfiguration shown in FIG. 6 may be also employed same as explained inpreferred embodiment 1.

Generally, when the head support device 2 moves the magnetic head to adesired track position at high speed, if torsional vibration occurs inthe load beam 22, as far as the relative positions of the slider 3 andthe peak 27 of the dimple 28 of the load beam 22 contacting therewithare invariable, off-track is not caused by the generated torsionalvibration, and the access time to the target track position can beshortened, and to realize such configuration, it is required to matchthe position of the peak 27 of the dimple 28 of the load beam 22 withthe neutral axis of torsion of the load beam 22, as already explained inpreferred embodiment 1. As also explained, when the position of the peak27 of the dimple 28 is defined at a position for forming the dimple 28in the plane 22 a of the load beam 22 and coinciding with the section ofthe load beam 22 and the center of shearing of each section parallel tothis section, the neutral axis of torsion is on a plane passing thepeaks of the two pivots 25 and the peak 27 of the dimple 28, and itfurther coincides with the line 31 passing the middle point of the linelinking the peaks of the two pivots 25 and the peak 27 of the dimple 28.

In the head support device 2 of the disk apparatus in preferredembodiment 4 of the invention, the side reinforcements 41 a, 41 b areprovided at both right and left sides, and the outer sides of theprincipal parts of the pi-shaped load beam 22 and flexure 21 are affixedto contact with each other, thereby forming an entire structure in anH-section, and its sections are symmetrical in both lateral directionand vertical direction, and therefore it is enough to match the centroidwith the peak 27 of the dimple 28, not the center of shearing of thesection of the structure in an H-shape combining the load beam 22 andflexure 21 integrally.

Therefore, in the head support device 2 of the disk apparatus inpreferred embodiment 4 of the invention, in order that the line 31 (seeFIG. 12) present on a plane passing three points, that is, the peaks oftwo pivots 25 of the carriage 4 and the peak 27 of the dimple 28 of theload beam 22, passing the middle point of the line linking the peaks ofthe two pivots 25, and at right angle to the line linking the peaks ofthe two pivots 25 may be the neutral axis of torsion of the load beam22, and also that the centroid of the section of the load beam 22 andeach section of the load beam 22 parallel to this section may be on theline 31, the side reinforcements 41 a, 41 b and the shape of the sidereinforcements 41 a, 41 b in the individual portions of the load beam 22are determined. In the load beam 22 having thus designed sidereinforcements 41 a, 41 b, the peak 27 of the dimple 28 of the load beam22 is not moved if torsional vibration occurs as indicated by brokenline in FIG. 14, and if the magnetic head is moved to a desired trackposition at high speed, off-track does not occur, and the access time tothe desired track position can be shortened.

In this configuration, the rigidity of the load beam 22 can besubstantially increased by the side reinforcements 41 a, 41 b, and theposition of the peak 27 of the dimple 28 of the load beam 22 is matchedwith the neutral axis of torsion of the load beam 22, and therefore ifthe setting height of the load beam 22, that is, the distance. betweenthe carriage 4 and the magnetic recording medium 1 fluctuates due tomanufacturing fluctuations, the resonance characteristic of the loadbeam 22 is stabilized in spite of impact or vibration due to externaldisturbance, or vibration due to seek motion of the magnetic head, andhigher resonance of torsion can be decreased, and off-track hardlyoccurs.

The head support device 2 having such configuration can be applied,needless to say, in all head support devices including the head supportdevice facing the upper side of the magnetic recording medium, and themagnetic head can be moved to a desired track position at high speed,and the disk apparatus shortened in the access time is realized. Hence,if the setting height of the load beam varies, the resonancecharacteristic of the load beam can be stabilized, and the sliderposition is not changes in spite of torsional vibration, and the headpositioning control characteristic can be enhanced.

In the head support device in preferred embodiment 4 of the invention,instead of the structure explained in preferred embodiment 2, that is,instead of forming the two pivots on the carriage as shown in FIG. 8 andFIG. 9, two pivots may be formed at right and left symmetrical positionsacross the centerline in the longitudinal direction of the load beam.

FIG. 15 and FIG. 16 are diagrams showing other structure of head supportdevice in preferred embodiment 4 of the invention, that is, samestructure as in preferred embodiment 2. FIG. 15 is a partially cut-awayside view of essential parts of the head support device, and FIG. 16 isa perspective view of the load beam as seen from the slider mountingside. In FIG. 15 and FIG. 16, same reference numerals are given to sameconstituent elements of preferred embodiment 2 shown in FIG. 8 and FIG.9. In the head support device of this structure, the load beam 22 andthe flexure 21 have side reinforcements 41 a, 41 b formed on almostentire surface of both right and left sides, and the structure has api-section, and both outer sides of principal parts, not the pi-shapedside reinforcements 41 a, 41 b of the load beams 22 and flexure 21, aremutually affixed to contact with each other, and an entire structure ofH-section is formed. Thus, what differs from preferred embodiment 2 isthat the side reinforcements 41 a, 41 b are formed and the pi-shapedload beam 22 and flexure 21 obtained, and other structures and actionand effect as the head support device are same as in preferredembodiment 2, and the explanation is omitted to avoid duplication.

Further, in the head support device in preferred embodiment 4 of theinvention, it may be also composed as explained in preferred embodiment3, that is, as shown in FIG. 10, without forming dimple in the load beamcontacting with the gimbals of the flexure mounting the slider, thedimple may be formed in the gimbals of the flexure having the slider. Inthe head support device of such configuration, same effects areobtained, that is, the resonance characteristic of the load beam 22 canbe stabilized in spite of impact or vibration, and higher resonance oftorsion can be decreased, and off-track occurs hardly.

Besides, the opening made of holes may be formed in part of the loadbeam 22 or the load beam may be formed by using a thin plate, andtherefore the head support device reduced in weight and size can berealized.

By mounting such head support device, further, the disk apparatus isenhanced in the head positioning control characteristic, capable ofmoving the magnetic head to a desired track position at high speed, andsubstantially shortened in the access time.

Preferred Embodiment 5

FIG. 17 and FIG. 18 are diagrams explaining the head support device of adisk apparatus in preferred embodiment 5 of the invention. FIG. 17( a)is a perspective view of essential parts showing a schematic structureof the head support device in preferred embodiment 5, and FIG. 17( b) isa perspective exploded view of essential parts showing a schematicstructure of the head support device in preferred embodiment 5. FIG. 18is a sectional view of a load beam 22 shown in a section of a planeperpendicular to the centerline 24 in FIG. 17( a) and passing a peak 27of a dimple 28. What preferred embodiment 5 of the invention differsfrom the foregoing preferred embodiments 1 to 4 is that a resin isoutserted in side reinforcements 161 at both sides of the load beam 22.In this composition, the weight of the load beam 22 is reducedsignificantly, and the resonance frequency can be enhanced. Moreover,when the neutral axis of torsion of the load beam 22 is matched with aline 31 linking the middle point of the line segment linking the peaksof a pair of (two) pivots 25 of the carriage 4 and the peak 27 of thedimple 28, the rib shape of the side reinforcement 161 can be designedat a higher degree of freedom by forming the resin. Further, the planeshape of the load beam 22 can be designed in other shape thantrapezoidal shape, and the load beam weight can be further reduced.

By mounting such head support device, further, the disk apparatus isenhanced in the head positioning control characteristic, capable ofmoving the magnetic head to a desired track position at high speed, andsubstantially shortened in the access time.

In the foregoing preferred embodiments 1 to 5, the head support deviceof the magnetic recording and reproducing apparatus using the magnetichead is explained, but same effects are obtained when used as the headsupport member and head support device in contact-free type diskrecording and reproducing apparatus, for example, such as optical diskapparatus or magneto-optical disk apparatus.

INDUSTRIAL APPLICABILITY

According to the head support device of the invention, as describedherein, the load beam and carriage contact with each other by means oftwo pivots, the slider mounted on the flexure and the load beam contactwith each other by means of a dimple, the slider mounting the headpresses against the recording medium, the center of shearing of thesection of the load beam by a plane perpendicular to the recordingmedium passing at least the peak of the dimple (or the centroid when thesection is symmetrical both vertically and laterally) coincides with thepeak of the dimple, and side reinforcements are provided at both edgesides of the load beam.

By such configuration of the head support device, if the setting heightof the load beam fluctuates, the resonance characteristic of the loadbeam can be stabilized, and the slider position is not changed in spiteof torsional vibration, and the head positioning control characteristicis enhanced, and further the access speed of moving the head to adesired track can be enhanced, and the access time can be shortened. Forexample, by reinforcing the rigidity of the load beam by composing sidereinforcements along the vicinity of the elastic member made of platespring or the like, an opening made of holes, for example, may be formedin part of the load beam, or the load beam or side reinforcement can beformed by using, for example, thin metal plate or resin, so that a headsupport device reduced in weight and size can be realized.

By mounting such head support device, further, the disk apparatus ofhigh reliability enhanced in the head positioning controlcharacteristic, capable of moving the head to a desired track positionat high speed, and substantially shortened in the access time can berealized.

1. A head support device comprising: a head, a load beam for supportingthe head, a bearing provided between the load beam and a carriage, andwherein the load beam is rotatable in a substantially perpendiculardirection to a recording medium, an elastic member for affixing the loadbeam to carriage, and side reinforcements provided in the load beam,wherein said elastic member is disposed between said carriage and saidload beam, so that an applied force for the load beam is generated in adirection perpendicular to said recording medium.
 2. A head supportdevice comprising: a head, a load beam for supporting the head, a dimpleprovided in the load beam, a bearing provided between the load beam anda carriage, and wherein the load beam is rotatable in a substantiallyperpendicular direction to a recording medium, an elastic member foraffixing the load beam to carriage, and side reinforcements provided inthe load beam, wherein said elastic member is disposed between saidcarriage and said load beam, so that an applied force for the load beamis generated in a direction perpendicular to said recording medium.
 3. Ahead support device comprising: a head, a load beam for supporting thehead, a bearing provided between the load beam and a carriage, andwherein the load beam is rotatable in a substantially perpendiculardirection to a recording medium, an elastic member for affixing the loadbeam to carriage, and side reinforcements provided in the load beam,wherein an opening is provided in the load beam, and wherein saidelastic member is disposed between said carriage and said load beam, sothat an applied force for the load beam is generated in a directionperpendicular to said recording medium.
 4. The head support device ofany one of claims 1 to 3, wherein gimbals is provided between a slidermounting the head and the load beam.
 5. The head support device of anyone of claims 1 to 3, wherein the bearing is provided in the carriage,and the peak of the bearing contacts with the load beam.
 6. The headsupport device of any one of claims 1 to 3, wherein the bearing isprovided in the load beam, and the peak of the bearing contacts with thecarriage.
 7. The head support device of any one of claims 1 to 3,wherein the elastic member is formed integrally with the load beam. 8.The head support device of any one of claims 1 to 3, wherein the bearingis composed of two pivots.
 9. The head support device of any one ofclaims 1 to 3, wherein the bearing is composed of a pair of pivots. 10.The head support device of any one of claims 1 to 3, wherein the loadbeam is rotatable about the bearing as the center of rotation.
 11. Thehead support device of any one of claims 1 to 3, further comprising asecond bearing rotatable in a radial direction on the recording medium,wherein the carriage rotates about the second bearing as the center ofrotation.
 12. The head support device of any one of claims 1 to 3,wherein the load beam is forced to a direction perpendicular to thesurface of a slider mounting the head by a thrusting force by theelastic member.
 13. The head support device of any one of claims 1 to 3,further comprising a flexure having a slider mounting the head disposedat an end portion of the load beam.
 14. The head support device of claim13, wherein the slider mounting the head is disposed in gimbals of theflexure.
 15. The head support device of claim 1 or 2, wherein the sidereinforcements are provided at both side edges of the load beam.
 16. Thehead support device of claim 15, wherein the side reinforcements aremade of resin.
 17. The head support device of claim 15, wherein the sidereinforcements are made of resin and are disposed in the load beam byintegral forming.
 18. The head support device of claim 1 or 2, whereinthe side reinforcements are provided at both side edges of the load beamby bending process.
 19. The head support device of claim 1 or 2, whereinthe height of the side reinforcements greater than the thickness of theload beam.
 20. The head support device of claim 18, wherein the shape ofthe section is like letter W at a section perpendicular to thecenterline in the longitudinal direction of the load beam.
 21. The headsupport device of claim 18, wherein the shape of the section is likeletter H at a section perpendicular to the centerline in thelongitudinal direction of the load beam.
 22. The head support device ofclaim 21, wherein the shape of the entire section is like letter H, byadhering members having a pi-shaped section, at a section perpendicularto the centerline in the longitudinal direction of the load beam. 23.The head support device of claim 2, wherein the bearing is composed oftwo pivots, and the side reinforcements are formed on a plane of theload beam, being perpendicular to the line linking the middle point ofthe two pivots and the peak of the dimple, with the center of shearingof the section of the load beam passing the peak of the dimple, being atthe same position as the peak of the dimple.
 24. The head support deviceof claim 2, wherein the bearing is compose of two pivots, and the dimpleprovided in the load beam has its peak on a perpendicular bisector ofthe line linking the peaks of the pivots.
 25. The head support device ofclaim 21, wherein the bearing is composed of two pivots, and the sidereinforcements are formed, being perpendicular to the centerline in thelongitudinal direction of the load beam, with the centroid at theposition of center of gravity of the section of the load beam passingthe peak of the dimple, being at the same position as the peak of thedimple provided in the load beam.
 26. The head support device of claim25, wherein the side reinforcements are formed at both side edges of theload beam, with the centroid at the position of center of gravity at thesection perpendicular to the centerline in the longitudinal direction ofthe load beam, positioned on a plane passing the peaks of the two pivotsand the dimple provided in the load beam.
 27. The head support device ofclaim 25, wherein the side reinforcements are formed at both side edgesof the load beam, with the centroid at the position of center of gravityat the section perpendicular to the centerline in the longitudinaldirection of the load beam, positioned on a line linking the middlepoint of the line linking the peaks of the two pivots and the peak ofthe dimple.
 28. The head support device of claim 3, wherein the openingis provided in the middle of the load beam.
 29. The head support deviceof claim 3, wherein the opening is formed symmetrically to thecenterline of the load beam.
 30. The head support device of claim 3,wherein the opening is formed in circular, elliptical or polygonalshape.
 31. The head support device of claim 3, wherein the opening isformed in a slit shape.
 32. The head support device of claim 3, whereinthe end portion of the opening is provided near the side reinforcements.33. The head support device of claim 3, wherein at least two openingsare provided, and each opening is formed at symmetrical position to thecenterline of the load beam.
 34. The head support device of any one ofclaims 1 to 3, wherein the bearing is composed of two pivots, and theload beam is provided with the balancer so that the direction of actionof the total center of gravity in the recording medium direction of theflexure having the slider, the rotating portion of the load beam and thebalancer may pass the axis of rotation linking the peaks of the pivots.35. A disk apparatus comprising: a recording medium, a head, a load beamsupporting the head, a bearing provided between the load beam and acarriage, and wherein the load beam is rotatable in a substantiallyperpendicular direction to a recording medium, an elastic member foraffixing the load beam to carriage, and side reinforcements provided inthe load beam, wherein said elastic member is disposed between saidcarriage and said load beam, so that an applied force for the load beamis generated in a direction perpendicular to said recording medium. 36.A disk apparatus comprising: a recording medium, a head, a load beamsupporting the head, a bearing provided between the load beam and acarriage, and wherein the load beam is rotatable in a substantiallyperpendicular direction to a recording medium, an elastic member foraffixing the load beam to carriage, and wherein an opening is providedin the load beam, and wherein said elastic member is disposed betweensaid carriage and said load beam, so that an applied force for the loadbeam is generated in a direction perpendicular to said recording medium.37. The disk apparatus of claim 35 or 36, wherein gimbals is providedbetween the slider mounting the head and the load beam.
 38. The diskapparatus of claim 35 or 36, wherein the bearing is provided in thecarriage, and the peak of the bearing contacts with the load beam. 39.The disk apparatus of claim 35 or 36, wherein the bearing is provided inthe load beam, and the peak of the bearing contacts with the carriage.40. The disk apparatus of claim 35 or 36, wherein the elastic member isformed integrally with the load beam.
 41. The disk apparatus of claim 35or 36, wherein the bearing is composed of two pivots.
 42. The diskapparatus of claim 35 or 36, wherein the bearing is composed of a pairof pivots.
 43. The disk apparatus of claim 35 or 36, wherein the loadbeam is rotatable about the bearing as the center of rotation.
 44. Thedisk apparatus of claim 35 or 36, further comprising a second bearingrotatable in a radial direction on a recording medium, wherein thecarriage rotates about the second bearing as the center of rotation. 45.The disk apparatus of claim 35 or 36, wherein the load beam is forced toa direction perpendicular to the surface of the slider by a thrustingforce by the elastic member.